function y = e_t1(x)
%Extended Tridiagonal-1 Function
%x0=[2,2,...,2] 
%fmin=n/2
%Author:shi yangyang
n=length(x);
m=n/2;
y=ones(1,m);
for i=1:1:m
    u(i)=x(2*i-1)+x(2*i)-3.0;
    v(i)=x(2*i-1)-x(2*i)+1.0;
    y(i)=u(i)^2+v(i)^4;
end
y=sum(y);